Personnel specialists, also known as human resources professionals, formulate policy and organize and conduct programs relating to all phases of personnel activity. Laborrelations specialists serve as mediators between employees and the employer. They represent management during the collective-bargaining process when contracts with employees are negotiated. They also represent the company at grievance hearings, required when a worker feels management has not fulfilled its end of an employment contract. There are approximately 502,730 human resources specialists and labor relations specialists employed in the United States.